Machine for sharpening twist-drills.



No."s'47,4|3. Patented Apr. l0, I900. M. c. JOHNSON.

MACHINE FOR SHARPENING TWIST DBILLS.

' (Applicati bn med Aug. 5, 189 8.) '(No Model.) 5 Sheets-Shee'l I.

m: nonms PETERS 00,, PHDTDUTHQ. wnsmnsrou. n. c.

No. 647.4!3. Patented Apr. I0, woo.

m. c. JOHNSON. MACHINE FOR SHABPENIVNG TWIST DRILLS.

(Application filed Aug. 5, 1898.)

5 Sheets-'-Sheet 2.

(No Model.)

\ l [I I I l k A US,

THE Norms PETERS co. Mom-uTnca.k WASHINGTON, u. c.

No. 647,4!3. Patented Apr. [0, 1900. m. c. JOHNSON. MACHINE FDRSHABPENING TWIST DRILLS.

(Applicafion filed Aug. 5, 1898.) (No Model.) 5 Sheets-Sha0i 3.

m: scams P'm'ms cc. PHo ro-uwo" WASHINGION. o. c.

No. 647,413. Patented Apr. I0, 1900.

m. c. ammsou.

MACHINE FUR SHABPENING TWIST DRILLS.

(Application filed Aug. 5,}898.)

5 Sheets-Sheet 4.

(No Model.)

THE Nbamsyrrzns 00.. Pgoruumo" WASHINGTON, a. c.

No. 647,413. Patented Apr.- l0, I900. M. C. JOHNSON.

MACHINE FOR SHARPENING TWIST DRILLS.

(Application filed Aug. 5, 1698,) (No Model.) 5 Sheets-Sheet 5.

THE NORRIS wrrzns (20.. wnorouma, WA$HINGYON. r:v c

rE STATES PATENT FFICE.

MOSES O. JOHNSON, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE WVIIITNEYMANUFACTURING COMPANY, OF SAME PLACE.

MACHINEFOR SHARPENING TWIST-DRILLS.

SPECIFICATION forming part of Letters Patent No. 647,413, dated April10, 1900.

Application filed August 5, 1898.

To all whom it'm/my concern:

Be it known that I, Mosns O. JOHNSON, a citizen of the United States,residing at Hartford, in the county of Hartford and State of grindingthe cutting-lips of twist-drills that have been dulled by use.

The object of the invention is to providea simple andconvenientmachinein which twistdrills of many different sizes may bequickly placed and accurately ground, so that their cutting-1i ps willhave the most desirable shape for efficient service.

The machine embodying this invention, which is illustrated in theaccompanying drawings, has a bed, a slide that is movable on the bedtoward and from the front and back, a carriage that is movable on theslide from side to side, a rotatable grinding-wheel that is mounted uponthe carriage, and connections whereby the wheel when in use may be keptwet. The bed also supports a swinging frame that bears adj ustablej awsfor grasp ing and holding the drills of various diameters that are to beground with their axes oblique to the periphery of the grinding-wheeland out of the plane of the axis of the swinging frame.

Figure 1 of the drawings shows a side elevation of such a machine. Fig.2 shows a plan of the machine. Fig. 3 shows a plan of the grinding-wheelcarriage with parts broken away to illustrate the means by which thegrinding-wheel may be adj ust-ed toward and from the front. Fig. 4 is aside elevation of the grinding-wheel carriage with parts broken away toillustrate the means by which the grinding-wheel may be adjustedsidewise. Fig. 5 is a plan of the bed and the swinging frame with thedrill-holding jaws. Fig. 6 is a side viewof the swinging frame. Fig. 7is a vertical section of the drill-holding jaws, showing the means foropening and closing, the section being taken on theplane indicated bythe dotted line as a: of Fig. 2. Fig.

8 is a larger view of the angular holding-jaw, illustrating thepositions occupied by drills Serial No 687,839. No model.)

of different diameters. Fig. 9 is a diagrammatic View illustrating themovement relatively to the grinding-wheel of a two-inch drill held bythe swinging frame, and Fig. 10 is a diagram indicating the manner inwhich the cutting-lips of a two-inch drill would be ground and clearedon this machine.

The bed 1 maybe mounted upon a column of any suitable design. Upon theupper face of the bed there'is an ordinarydovetail guideway, and held bythis guideway so that it may be moved from back to front is a slide 2.This slide upon its upper face has asimi-' lar guideway that extends atright angles with the gnideway upon the bed, and held by this guidewayon the slide is a carriage 3, r

Fig. 1.

A ledge 4 projects from the front of the bed, and secured to this is ablock 5. Supported against longitudinal movement in a perforation inthis block is aspindle 6,thatonits outer end is provided with ahand-wheel 7 and that has its inner end threaded and fitted intoathreaded perforation in the wall of the slide. Turning the hand wheel 7moves the slide alongthe guideway on the top of the bed toward the frontor back, according to the direction of rotation of the wheel, Fig. 3.

Projecting upwardly from a part secured to the top of the bed are lugs8, and supported by perforations (one of which is threaded) in theselugs is a threaded rod 9, that has its outer end provided with afinger-head l0 and its inner end arranged to engage the wall of theslide. By turning the head 10 in the proper direction the inner end ofthis rod 9 may be set in the correct positionto stop the slide in thenecessary position, Fig. 3.

A perforated hub 11 is attached to one side of the carriage, and in thisturns a spindle 12, that 011 its outer end bears a crank 13 and on itsinner end a spur-pinion 14:. A rack 15 is attached to the under side ofthe carriage in position to be engaged by the teeth of the pinion.Turning the crank through the pinion and rack moves the carriage fromside to side of the bed, Fig. 1. p

In adjustable bearings in blocks 16 on the top of the carriage is ashaft bearing a grinding-wheel 17 and a pulley 18, around which thedriving-belt for rotating the grindingj that has a long horizontal arm38.

wheel is passed. Supported by the carriage and extending around aportion of the periphery and the faces of the grinding-wheel, near theperiphery, is a water-shield 19. This shield is formed in twoparts,which are hinged together so that the upper part may be turnedback away from the periphery of the grinding-wheel, Fig. 4.

At the base of the column is a rotary pump 20. This pump may be rotatedby passing'a belt from a counter-shaft around a pulley 21 on thepump-shaft and the pulleys 22 on an arbor supported by the arms of afork 23, mounted on the pump. A flexible tube 24 may be led from anopening in the casing of the pump to a nipple 25, that opens through thetop of the water-shield, so that water may be forced to the periphery ofthe grindingwheel, Fig. 1.

The upper face of the carriage preferably has low side walls, so as toform a tray 26 for collecting the water that drips from the wheel.

A spout 27 is'provided to direct the flow of water from this tray into ashallow receptacle 28, formed at the rear of the slide. From thereceptacle in the slide there is a spout 29 to direct the water into thepan 30, secured to the rear of the bed. From this pan a pipe 31 leads tothe supply-tank 32, from which water is drawn by the pump. By means ofthese connections no matter to what position (toward the front or backor toward either side) the grinding-wheel is adjusted a plentiful amountof water may be supplied to the periphery of the grinding-wheel, andafter having performed its function the water will fiow back into thesupply-tank, Figs. 1 and 2.

The bed is extended outwardly toward the front and toward one side, andupon these extended portions, are blocks 33, secured to the upper facesof which are bearing-posts 34, that hold the pivot-studs for a swingingframe 35. The bearing-posts are preferably so located and thepivot-studs so arranged that the axis of the swinging frame extends in aplane a little above the axis of the grindingwheel, as illustrated inFig. 1, at an angle of about forty-five degrees to the axis of thegrinding-wheel, as illustrated in Fig. 2.

The upper part ofthe frame is arched, so as to give suitable room forthe jaws which it supports and to provide a convenient portion forgrasping and swinging the frame. The lower part of the frame near oneend is provided with an ordinary dovetailed guideway 36. Movable uponthis way is a slide 37, This arm has a dovetailed way 39, and on thisare an angular holding-jaw 40, a guiding-jaw 41, and a gage-plate 42.Each of these is adjustable along the way and is clamped in position bya thumb-nut 43, that turns upon a threaded stud, so as to tighten orloosen a clamp-plate 44. The jaw-slide 37 has a dovetailed guideway45,by which the complementary j aw-slide 46 is retained. slide ispreferably straight and forms the re- The front edge of this lattertaining-jaw 47, Figs. 2 and 7. Secured to the swinging frame 35 at theend of the guideway 36 is a plate 48, and held by this plate againstlongitudinal movement is a spindle 49. This spindle has a hand-wheel 50on its outer end and is provided with a left-hand screw-thread 51 of onepitch and aright-hand screw-thread 52 of one-half the pitch of theother, Fig. 7. The screw-thread 51 fits a threaded perforation in a partof the jawslide 46 and the screw-thread 52 fits a threaded perforationin a sleeve 53, that is secured to the jaw-slide 37. When the hand-wheelis rotated, the jaw-slides, with the jaws, are moved toward or from eachother, according to the direction of rotation of the wheel, the jaw 40moving lip-half as fast as the jaw 47. The jaw 40 is adjusted, until itis in the correct position for properly holding the drills, by turningthe sleeve 53, and then the sleeve is fastened against further movement,Fig. 7.

The guiding-jaw is a plate with an angular opening similar in shape tothe angular opening of the holding-jaw and it is provided for assistingthe support of drills of large size. The gage-plate is employed when anumber of drills of the same length are to-be ground and it is desiredto facilitate their setting, so that they will be ground uniformly.Attached to the side of the lower part of the swinging frame is a finger54, that is arranged to engage with the edge of one of the grooves, soas to correctly locate the cutting-lip that is to be ground withrelation to the grindingwheel, Fig. 2.

After one lip has been ground the jaws are loosened and the drill turnedover and the other lip located by the finger and gage-plate in positionto beground.

Projecting upwardly from the bed is a post 55, and held by the top ofthis post is a rotatable disk 56. A curved runner 57 is secured to theunderside of the swinging frame, so as to rest upon this disk, whichforms an antifriction-support when the frame is swung and prevents anyyielding of the jaws when a drill is being ground, Fig. 1.

The jaws are so located and arranged upon the swinging frame that theywill hold drills that are placed between them with their axes in a planeslightly below and extending at an angle of about fifteen degrees withthe axes of the swinging frame-that is, the axes of the drills willextend substantially at an angle of sixtydegrees with the axis ofthe'grinding-wheel.

In Fig. 9 the broken line 60 represents the axis of the swinging frame,the line 61 the axis of the drill at the commencement of grinding, andthe line 62 the position that the drill-axis would occupy with relationto the axis of the wheel if the frame were rotated one hundred andeighty degrees. Each particle of the cutting-lip 63 of the drill thatengages the peripheral face 64 of the grindingwheel moves on the are ofa circle when the frame is swung.

If the axis of the drill were concentric with'the axis of the frame, atrue cone would be ground upon the end of the drill; but as the axis ofthe drill is below the plane of the axis of the frame, so that the axisof the frame and the axis of the drill are eccentrio as well as atangles with each other, the end of the drill between the grooves isground so as to give clearance to the cutting-lip.

In Fig. 10 the point GOrepresents the axis of the swinging frame, thepoint 61 the axis of the drill, the point 65 the outer edge of thecutting-lip, and the line 63 the cutting-lip of the drill. If the pointwere in the same plane as the point (Bl-that is,'if thepoint 60 were at68the axis of the frame and the axis of the drill would be in the sameplane, and revolving the cutting-lip sixty degrees would carry the point61 to 66 and the point to 67'and the line 63 to the position of line 69.In other words, a true conical surface would be formed on the end of thedrill. However, as the axis of the frame is above the plane of the axisof the drill the point 61 will in moving sixt-y degrees on the center 60swing to 71, and the point 65 will swing to 72, and the line 73 willrepresent the cutting-lip. The angle 74: represents the amount groundfrom the outer edge of the drillthat is, it is the angle of clearance ofthe outer end of the cutting-lip-while the angle 75 represents theamount ground from the point end of the cutting-lip--that is, it is theangle of clearance of the point and of the cutting-lip. These angles ofclearance, as shown, depend upon the distance the axis of the drill isbelow the axis of the swinging-frame and the distance the axis of thedrill at the point is to one side of the axis of the swinging frame.

The smaller drills do not need as much clearance as the larger drills,yet the angle of clearance should be in all sizes substantially thesame. For the purpose ofigrinding clearance according to the size of thedrills the angle that the lowerpart 0f the drill-holding jaw makes withrelation to a horizontal plane is greater than the angle that the upperpart of the jaw makes, so that the smaller the drill the more its axiswill be raised toward the plane of the axis of the swinging frame, andas the angular jaw moves much slower than the other jaw the smallerdrills will be held with their points nearer to the axis of the swingingframe, as well as in a higher plane. By these means the angle ofclearance remains substantially the same for drills of all sizes; but ofcourse the amount of clearancefor large drills is greater than for smalldrills. The angle of clearance with this machine for the point end ofthe cuttinglips of these drills is somewhat greater than theangle ofclearance of the outer edge of the cutting-lip, so that a point isformed that when put to use begins to drill immediately.

This machine can be adjusted so that the grinding will be very accurate,and the parts are firm, so that the lips that are ground will beperfectly formed. Drills of all sizes can be quickly put into the jawsof this machine and rapidly ground, so that the cutting-lips will havethe correct clearance for the most efficient service, and a large numberof drills can be rapidly ground alike.

I claim as my invention- 1. In a drill-grinding machine in combination,a bed, a grindingwheel arranged to rotate on a horizontal axis, mountedupon the bed, a frame, mounted upon the bed so as to oscillate on ahorizontal axis that is higher than, and projects at an angle withrelation to the axis of the grinding-wheel, and a drillholder mountedupon the swinging frame so as to hold a drill with its axis extendinghorizontally at an" angle with the horizontal axis of the frame and at adifferent angle with the horizontal axis of the grinding-wheel,substantially as specified.

2. In a drill-grinding machine in combination, a bed, a slide movableuponthe upper surface of the bed, a grinding-wheel arranged to rotate ona horizontal axis and move with the slide, a frame mounted upon the bedso as to oscillate on a horizontal axis that is higher than, andprojects at an angle with the axis of the grinding-wheel, and adrill-holder mounted upon the swinging frame so as to hold a drill withits axis extending horizontally at an angle with the horizontal axis ofthe frame, and at a different angle with the horizontal axis of thegrinding-wheel, substantially as specified.

3. In a drill-grinding machine in combination, a bed, a slide movableupon the upper surface of the bed, a carriage movable with the slide andalso at right angles thereto, a grinding-wheel arranged to rotate on ahorizontal axis and move with the slide and with the carriage, a framemounted upon the bed so as to oscillate on a horizontal axis that ishigher than, and projectsat an angle with the axis of thegrinding-wheel, and a drill-holder mounted upon the swinging frame so asto hold a drill with its axis extending horizontally at an angle withthe horizontal axis of the frame and at a different angle with thehorizontal axis of the grinding-wheel, sub stantially as specified.

4. In a drill-grinding machine in combina tion, a bed, a rotarygrinding-wheel mounted upon the bed, a swinging frame mounted upon thebed with its axis at an angle with the axis of the grinding-wheel, andan angular holding-jaw mounted upon the swinging frame, theholdiug'sides of which jaw incline differently with relation to ahorizontal plane whereby the smaller the diameter of the drill placed inthe jaw, the nearer will its point be to the axis of the frame,substantially as speci 5. In a drill-grinding machine in combination, abed, a rotary grinding-wheel mounted upon the bed,a swinging framemounted upon the bed with its axis at an angle with the axis of thegrinding-wheel, anda pair of drill-holdin g jaws movable toward and fromeach other upon the swinging frame, one of said jaws having an angularopening, the sides of which opening incline differently with relation toa horizontal plane whereby the smaller the diameter of the drill placedin the jaw, the higher and farther in will be its axis, substantially asspecified.

6. In a drill-grinding machine in combination, a bed, a rotarygrinding-wheel mounted upon the bed, a swinging frame mounted upon thebed with its axis at an angle with the axis of the grinding-wheel, a jawwith an angular drill-holding opening and a retaining-jaw movablymounted on the swinging frame, and means for simultaneously moving thejaws toward and from each other at different rates of speed,substantially as specified.

7. Ina drill-grinding machine in combination, a bed, a rotarygrinding-Wheel mounted upon the bed, a swinging frame mounted upon thebed with its axis at an angle with the axis of the grinding-wheel, a jawwith an angular drill-holding opening, a retaining-jaw, means forsimultaneously moving the holding and retaining jaws toward and fromeach other at different rates of speed, and a guiding-jaw movable withthe holding-jaw, said holdingjaw, retaining-jaw and guiding-jaw beingmounted upon the swinging frame, substantially as specified.

8. In a drill-grinding machine in combina tion, a bed, a rotarygrinding-wheel mounted upon the bed,aswinging frame mounted upon the bedwith its axis at an angle with the axis of the grinding-wheel, a jawwith an angular drill-holding opening, a retaining-jaw, means forsimultaneously moving the holding and retaining jaws toward and fromeach other at different rates of speed, said jaws being mounted upon theswinging frame, and a locating-finger mounted independently of the jawsupon the swinging frame, substantially as specified.

9. In a drill-grinding machine in combination, a bed, a rotarygrinding-wheel mounted upon the bed,a swinging frame mounted upon thebed with its axis at an angle with the axis of the grinding-wheel, a jawwith an angular drill-holding opening, a retainin g-j aw, means forsimultaneously moving the holding and retaining jaws toward and fromeach other at different rates of speed, and a gage-plate moving with theholding-jaw, said jaws and plate being mounted upon the swinging frame,substantially as specified.

10. In a drill-grinding machine in combination, a bed, a rotarygrinding-wheel mounted upon the bed,a swinging frame mounted upon thebed with its axis at an angle with the axis of the grinding-wheel, a jawwith an angular drillholding opening, and a retaining jaw movablymounted upon the swinging frame so as to hold a drill with its axis atan angle with and below the plane of the axis of the swinging frame, andmeans for simultaneously moving the jaws toward and from each other atdifferent rates of speed,'the angular opening of the holding-jaw beingsuch that the smaller the diameter of the drill placed therein, thehigher its axis will be, substantially as specified.

11. In a drill-grinding machine in combination, a bed, a grinding-wheelarranged to rorate on a horizontal axis upon the bed, a pump adjacent tothe bed, a water-shield inclosing a portion of the grinding-wheel,connections between the pump and the water-shield, a frame mounted uponthe bed so as to oscillate on a horizontal axis that ishigher than andprojects at an angle with the axis of the grinding-Wheel, and adrill-holder mounted upon the swinging frame so as to hold a drill withits axis extending horizontally at an angle with the horizontal axis ofthe frame and at a dilferent angle with the horizontal axis of thegrinding-wheel, substantially as specified.

12. In a drill-grinding machine in combination, a bed, a slide movableupon the upper face of the bed, a carriage movable with'the slide andalso at right angles thereto, a grinding-wheel arranged to rotate on ahorizontal axis and moved with the slide and with the carriage, a pumpadjacent to the bed, a watershield inclosing a portion of thegrindingwheel, a connection between the pump and the water-shield, areceptacle formed on the top of the carriage for collecting the waterthat drips from the grinding-wheel, a receptacle formed on the top ofthe slide for receiving water from the carriage-receptacle, a receptacleformed on the bed for receiving water from the slide receptacle, aconductor leading from the bed-receptacle to a watertank, a framemounted upon the bed so as to oscillate on a horizontal axis that ishigher than and projects at an angle with the axis of thegrinding-wheel, and a drill-holder mounted upon the swinging frame so asto hold a drill with its axis extending horizontally at an angle withthe horizontal axis of the frame and at a different angle with thehorizontal axis of the grinding-wheel, substantially as specified.

13. In a drill-grinding machine,in combination, a rotary grinding-wheelmounted upon the bed, a swinging frame mounted upon the bed with itsaxis at an angle with the axis of the grinding-Wheel, an angulardrill-holding jaw and a curved runner mounted upon the swinging frame,and a rotatable disk supported by the bed beneath the curved runner,substantially as specified.

MOSES O. JOHNSON.

Witnesses:

HARRY R. WILLIAMS, E. J. HYDE.

